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<html lang="en">
<head>
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    <title>Document</title>
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<body>
    <div id="test">
        
    </div>
    <script type="text/babel">
        class MyComponent extends React.Component{
            render(){
                return <h2>我是用类定义的组件(适用于[复杂组件]的定义)</h2>
            }
         }
         ReactDOM.render(<MyComponent/>,document.getElementById('test'))

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